[CRIU] CRIU saving/restoring fd for the device file

[Pavel Emelyanov]

On 10/02/2014 07:37 PM, Zmudzinski, Krystof C wrote:
> If the app runs uninterrupted by criu suspend/restore, each sys call to the driver works
> just fine: open returns valid fd and icotls return 0.  Also, errno is always 0.  After criu
> restore, open and ioctls still work and return valid fd and 0 respectively but errno is set to EINTR.  

Hm... Interesting. OK, I'll try to investigate what's going on.
Thanks for the report :)

> Krystof
> 
> -----Original Message-----
> From: Pavel Emelyanov [mailto:xemul at parallels.com] 
> Sent: Thursday, October 2, 2014 8:17 AM
> To: Zmudzinski, Krystof C; CRIU
> Subject: Re: [CRIU] CRIU saving/restoring fd for the device file
> 
> On 10/02/2014 07:08 PM, Zmudzinski, Krystof C wrote:
>> I have finally figured out that I can indeed talk to the driver just 
>> fine.  The problem is that my code checks for errno even when ioctls 
>> don't return -1.  For some reason, after resume, errno is set to 
>> EINTR.  Is it possible that criu causes this by sending a signal to the my app during suspend?
> 
> I doubt this. errno is just a variable in memory, criu doesn't touch the app's memory.
> 
>> Shouldn't errno be cleared by criu on resume?
> 
> AFAIK no, app's memory should be left intact on restore.
> 
> Can you describe problem in more details, please?
> 
> Thanks,
> Pavel
> 
> 
> 
> _______________________________________________
> CRIU mailing list
> CRIU at openvz.org
> https://lists.openvz.org/mailman/listinfo/criu
>